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1.
Foliar analysis was undertaken in two plots of Picea abies (L.) Karst., located in a watershed of Haute Ardenne, Belgium, in order to estimate the decline of the trees. Apart from a general Mg deficiency, the concentrations of the needles were in the same range as those determined in other European stands. Comparisons between healthy and declining trees within each plot revealed a general pattern of decline similar to that observed elsewhere in Western Europe. This was shown as lower Ca, Mg, Zn concentrations and water content and higher N and P concentrations of the needles collected from declining trees. It is concluded that this decline could be due to N over fertilization by the atmospheric deposition. The difference of decline between the two plots was attributed to the turnover rate of the soil organic layer which was less intensive in the most damaged plot.  相似文献   

2.
Two subsamples of healthy and declining trees of the same spruce stand were studied for their biomass and mineral content. Calcium and Mg content of the stand was found to be of the same order of magnitude as the total amount of these elements on the exchangeable capacity of the soil. This result shows that on poor soils fast growth of young stands is a powerful factor influencing soil impoverishment and acidification. The difference between the Ca and Mg content of yellow and green trees is equal to the amount of these elements which is taken up by the green trees during a 2 yr period.This suggests that this difference is the result of a rather long term trend of inadequate nutrient uptake.The evolution of Ca and Mg concentrations in relation to age of needles shows that declining trees support their growth by concentrating their Ca and Mg supply into the growing organs.  相似文献   

3.
Two subsamples of healthy and declining trees of the same spruce stand were studied for their biomass and mineral content. Calcium and Mg content of the stand was found to be of the same order of magnitude as the total amount of these elements on the exchangeable capacity of the soil. This result shows that on poor soils fast growth of young stands is a powerful factor influencing soil impoverishment and acidification. The difference between the Ca and Mg content of yellow and green trees is equal to the amount of these elements which is taken up by the green trees during a 2 yr period. This suggests that this difference is the result of a rather long term trend of inadequate nutrient uptake. The evolution of Ca and Mg concentrations in relation to age of needles shows that declining trees support their growth by concentrating their Ca and Mg supply into the growing organs.  相似文献   

4.
Nutrient status in Pinus radiata sites in the Basque Country (Spain) have been established. Current-year, 1-year-old needles, and soil samples were collected in 7 sites. Needle samples were analyzed for calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P) and nitrogen (N). Soil samples were analyzed for pH (H2O), N, P, Ca, Mg, K and aluminium (Al). The results indicate differences between sites and needles of different ages. In general, nutrient concentrations in needles are sufficient for the nutritive requirements, but some low concentrations of Mg and P found in 1-year-old needles, indicate that some trees may show signs of deficiency in the near future. In turn, N concentrations are, in many cases, higher than those usually found in this species and may originate growth disorders. These concentrations may be related to NO3 ? and NH4 + deposition. Soil nutrients are sufficient for trees requirements, but the levels of K and Mg are low. Soil pH values are not very acid, and the value of the Ca/Al ratio is, in general, near 1. An arrangement of sites and physiographical and nutritional parameters based on correlation and principal component analysis is also presented.  相似文献   

5.
Abstract

A study was made of the comparative nutrient content of healthy and declining sweet orange trees. Leaves were analysed for 12 elements using Kjeldahl and Spectrographic methods. No statistical differences were observed between healthy and declining trees in their content of N, P, Mg, Na, Mn, Fe, B, Cu, Mo, and Zn. Significant differences were obtained for K and Ca; healthy Blood Red trees were found to be lower in K but higher in Ca than declining trees. Phosphorus content was observed to be borderline to low in both healthy and declining trees. Magnesium was low to deficient. Boron content was high to excessive in most orchards regardless of tree condition.  相似文献   

6.
The objective of the investigation was to determine the effectsof sewage sludge application on nutrient concentrations in soil and plant biomass fractions in Scots pine forests (Pinus sylvestris, L.), situated on sandy soils with low pH, in a south to north temperature gradient in Sweden. Twenty tons dw ha-1 of sewage sludge was applied in 50 to 60 yr old pine forests at foursites from Brösarp in South Sweden to Jukkasjärvi in thenorthern parts of the country.Application of 20 ton dw ha-1 of sewage sludge significantlyincreased the concentrations of extractable N, P, K, Ca, Mg and Na, in both the mor layer and in the upper 10 cm of the mineral soil. Three years after sludge application K concentrations were only significantly increased in the upper 10 cm of the mineral soil. After 11 yr the concentrations of P were still at the samelevel in the mor layer as after three years. The concentrations of Ca, Mg and Na had slightly decreased only in the mor layer. There was, in most cases, a statistically significant positive correlation between the amount of applied sludge and nutrientconcentrations in the soil, as well as in pine needles and in leaves of Vaccinium vitis-idaea.In all sites, Mg concentrations in the mor layer was positivelyand significantly correlated with Mg concentrations in current-year pine needles. Similarly, concentrations of Ca, Mg,and P in the mor layer were correlated with concentrations of these elements in current-year shorts of Vaccinium vitis-idaea.  相似文献   

7.
The vigor of Norway spruce stands in the Bohemian Forest of Austria was correlated with site factors, informations on historic land use, and chemical properties of the soils and spruce needles. The study confirmed that trees on west exposed slopes and plateaus in higher elevation have lower crown densities. The soils in the area are generally low in base saturation. Historical land use, such as litter raking, grazing and burning of biomass for potash led to nutrient depletion. Increasing deposition of atmospheric N during the last decades alleviated N stress, but increased Ca and Mg stress. N∶Mg ratios in needles of declining stands are wide, indicating N induced nutritional imbalances. PH values in the mineral topsoil are very low on W-slopes and plateaus. Measurements of pollutant deposition at three different sites indicate a strong influence of aspect and elevation on input rates. In a southwest exposed stand and a stand on a hilltop, facing the prevailing winds, substantially more S and N was recovered in the throughfall than in northeast exposed stand. Deposition rates in the open did not differ significantly. High NO3 ? concentrations in the soil solution of the southwest exposed site indicate N saturation of the system. In order to test the hypothesis that mineral deficiency and nutritional disorders contribute to the poor vigor of these stands, fertilizer experiments were established. Fertilization with a combination of an organic fertilizer (BACTOSOL**)) and a magnesite fertilizer (BIOMAG*)) significantly improved crown density, growth, seed viability, and mineral nutrition as inferred from foliar analysis. NO3 ? leaching in the combined BACTOSOL+BIOMAG treatment increased during the first and second growing season after fertilization but leveled off to values typical for the control plots after three years. Mg content of the soil solution increased both in the BIOMAG and the combined BACTOSOL+BIOMAG treatment. These experiments show that the nutritional status and the resilience of declining forests in the Bohemian Forests of Austria can be easily improved by proper fertilizer treatment.  相似文献   

8.
Abstract

The seasonal patterns of foliage nutrient concentrations and contents were monitored for two growing seasons in an 11‐year—old Pinus el1iottii stand. In the first growing season after needle initiation, N, P, K, Mg, and Zn concentrations decreased, but this was followed by an increase in the fall and winter months. Another drop in concentration of all elements, except P, occurred in the second growing season. Decreases in total contents indicated that this drop was a result of translocation to other tissues. In contrast to the mobile elements, the concentration and fascicle contents of Ca, Mn, and Al increased with aging of the needles.

Between‐tree variability was least for N, P, and Zn and the N, K, Mg, Mn, and Zn in the current foliage had consistently lower variation than that in the 1‐year‐old foliage. Between‐tree variation for K was lower in the winter than the spring.

For pine foliage, recommended sampling period for N, P, Mg, and Zn is mid to late summer and for the other elements it is late fall to late winter.

There are several sources of variation that influence the level of nutrients in tree foliage. The most important of these, apart from the tree nutrient status, are seasonal fluctuations, variation between trees, and age of needles . Smaller sources of variation are associated with position of the needles within the crown, diurnal changes, year to year variation, and analytical errors1,2. These variables must be studied in order to develop suitable sampling techniques and in Pinus this has been undertaken for P. banksiana 1, P. taeda 3, P. strobus 4, P. resinosa 4, P. sylvestris 5, and P. radiata 6,7. However, foliage sampling has not been studied in detail for slash pine (Pinus elliottii Englem var. elliottii) and earlier studies with other pines have been largely confined to temperate or cool climates.

This study reports the variation in elemental concentrations with season, age of foliage, and between slash pine trees growing in a subtropical climate in Florida.  相似文献   

9.
Interest in mixed‐species plantations in the tropics has increased because they appear to provide a wider range of options, such as yield, biodiversity, nutrient cycling, and C sequestration than pure stands. Pure stands of Pinus patula Schlecht. and Charm., Juniperus procera Hochst., and Grevillea robusta A. Cunn., and mixed stands of P. patula/G. robusta, P. patula/J. procera, and P. patula/Podocarpus falcatus R. Br. at Wondo Genet in S Ethiopia were studied to examine (1) the impact of mixed‐species plantations on soil chemical properties, and (2) the impact of mixed‐species plantations on the nutritional status of constituent trees. Soil (0–50 cm depth) and foliage samples were collected from four random plots (100 m2) in each of the pure and mixed‐species plantations. Soil samples were analyzed for organic C, N, and base cations. Foliage samples were analyzed for nutrients (N, P, K, Ca, and Mg). There were little significant differences in soil chemical properties and foliar nutrient concentrations of trees between the pure and mixed stands. Among pure stands, J. procera and G. robusta differed in soil exchangeable Ca++ and K+ at 0–5 cm soil depth and in foliar P and Ca concentration. After 18 and 24 y, mixed stands did not influence soil chemical properties and tree nutrition differently than pure stands. This may be due to additive interaction in mixed‐species stands and the similarity of the constituent tree species in foliar nutrient concentration and their impact on soil chemical properties.  相似文献   

10.
ABSTRACT

Standards of optimum nutrition are not readily available for mature trees of the Canadian boreal forest. The objective of this study was to determine foliar nutritional standards for white spruce for all major nutrients [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and manganese (Mn)] using critical values (CVA) and compositional nutrient diagnosis (CND). Trees were sampled at two locations in Ontario and Quebec to cover a gradient of soil fertility levels. A boundary-line approach was used in combination with quadratic regression models to estimate the relationship between growth and foliar-nutrient concentrations or CND scores when free of the effects of interacting environmental factors. White spruce optimum nutrition ranges were computed from significant relationships (P ≤ 0.10) for N, P, K, Ca, and Mn concentrations and for N, P, and K CND scores. Optimum concentrations for first-year needles were 12.3, 1.9, 7.3, 6.5, and 0.39 mg g?1 for N, P, K Ca, and Mn, respectively, whereas optimum CND scores were 0.17, ?1.65, ?0.40, and ?0.30 for N, P, K, and Ca, respectively. Samples from a broader range of environmental conditions will be required in order to establish standards for all major nutrients and to ascertain toxicity levels of most nutrients.  相似文献   

11.
The decrease in anthropogenic deposition, namely SO42— and SO2, in European forest ecosystems during the last 20 years has raised questions concerning the recovery of forest ecosystems. The aim of this study was to evaluate if the long term data of element concentrations at the Fichtelgebirge (NE‐Bavaria, Germany) monitoring site indicates a relationship between the nutrient content of needles and the state of soil solution acidity. The soil at the site is very acidic and has relatively small pools of exchangeable Ca and Mg. The trees show medium to severe nutrient deficiency symptoms such as needle loss and needle yellowing. The Ca and Mg concentrations in throughfall decreased significantly during the last 12 years parallel to the significant decline in the throughfall of H+ and SO42— concentrations. Soil solution concentrations of SO42—, Ca and Mg generally decreased while the pH value remained stable. Aluminum concentrations decreased slightly, but only at a depth of 90 cm. Simultaneously a decrease in the molar Ca/Al and Mg/Al ratios in the soil solution was observed. Ca and Mg contents in the spruce needles decreased, emphasizing the relevance of soil solution changes for tree nutrition. The reasons for the delay in ecosystem recovery are due to a combination of the following two factors: (1) the continued high concentrations of NO3 and SO42— in the soil solution leading to high Al concentrations and low pH values and, (2) the decreased rates of Ca and Mg deposition cause a correlated decrease in the concentration of Ca and Mg in the soil solution, since little Ca and Mg is present in the soil's exchangeable cation pools. It is our conclusion that detrimental soil conditions with respect to Mg and Ca nutrition as well as to Al stress are not easily reversed by the decreasing deposition of H+ and SO42—. Thus, forest management is still confronted with the necessity of frequent liming to counteract the nutrient depletion in soils and subsequent nutrient deficiencies in trees.  相似文献   

12.
Abstract

The nitrification inhibitor dicyandiamide (DCD) offers potential for improving efficiency of N applications to cotton grown on sandy soils of the southeastern Coastal Plain. Research has indicated that cotton is sensitive to DCD. The purpose of this greenhouse experiment was to investigate the effect of DCD on growth and nutrient uptake of DPL 90 cotton grown for 73 days in pots containing a typical Coastal Plain soil (Norfolk sandy loam, Typic Paleudult). Nitrogen (50 mg kg‐1) as NaNO3 or urea, and DCD (0, 2.5, 5, 10, 15 and 20 mg kg‐1) were applied to the soil at first true leaf and plants were harvested 58 days later. Sodium nitrate increased leaf dry weight and total dry weight of plants 9.1 and 6.0%, respectively, over urea fertilized plants. Leaf area, dryweight, and stem dry weight were reduced linearly with DCD. Fertilization with urea increased concentrations of leaf P, K, and Mn and reduced the concentration of Mg in leaf tissue. Dicyandiamide increased leaf N, P, and K concentrations but reduced concentrations of Ca, Mg, and Mn. Uptake rates (μg‐1 g‐1 fresh root day‐1) of Ca and Mg were increased 7.5 and 13.7%, respectively, with NaNO3 vs. urea, while P uptake rate was 15.5% greater for urea‐fertilized plants vs. NaNO3‐fertilized plants. Dicyandiamide reduced Ca and Mg uptake rates. Phosphorus uptake rates were increased by DCD when urea was the N source. The effects of DCD on cotton growth and nutrient uptake generally resulted from the compound itself and were not an indirect result of nitrification inhibition. Although significant reductions in plant growth did not occur unless DCD exceeded that normally applied with recommended N rates on this soil, these results suggest a need for caution when applying DCD to cotton grown on sandy soils.  相似文献   

13.
Two Ca‐efficient and 3 Ca‐inefficient tomato lines selected on the basis of dry matter production, Ca concentrations in tissues, and severity of Ca deficiency symptoms were grown in nutrient solutions containing 6 levels of total Ca ranging from 15 to 365 mg in 70 mg increments. All lines responded to increased Ca supply by increasing in dry weight and by accumulating Ca. The critical Ca concentrations in the shoots were 0.25% and 0.40% on a dry weight basis for the efficient and inefficient lines, respectively. Concentrations of Ca, K, Mg, P, and NO3 were lower in shoots and except for Mg were lower in roots of efficient plants than in the inefficient plants. For all lines as more Ca was available in the media and as Ca increased in the shoots and roots, the concentrations of the nutrients other than Ca declined. The declines in concentrations of K and Mg were not due to dilution by higher dry matter production in the efficient lines relative to the inefficient ones, although the total accumulation of Ca, P, and NO3 did not vary with Ca supplied. Antagonism among cations may account for differences in efficiency among lines of tomato.  相似文献   

14.
A field plot experiment on fertilization with N, Mg and P in Scots pine forest was established. The experiment had a factorial design with three levels of N (0, 30 and 90 kg ha?1), two levels of Mg (0 and 1.5 kg ha?1) and two levels of P (0 and 5.3 kg ha?1). The application was done annually. There was a significant growth increase for the two N treatments. During a period of 5-years the mean increase in volume increment was 2.3 and 4.5 m3 ha?1 for the 30 N and 90 N kg ha?1 yr?1 treatments, respectively. This represents a percentage increase in volume increment of 53 and 102% compared to the untreated control plots. No significant growth effect of P and Mg application was detected, either alone or in combination with N. The needle nutrient concentrations have been followed along with the annual measurements. An increase in N-concentration was detected after the first growing season in the N treated trees. After five years the Mg concentrations in the needles are lower in these treatments. The one year old needles have concentrations as low as 0.05% Mg. No visible deficiency symptoms have been observed. The field experiment effects demonstrates that N is still the most limiting nutrient under these conditions and that there is a relative large potential for N accumulation in these forest types without negative effects.  相似文献   

15.
Abstract

Elemental concentrations of N, P, K, Ca, Mg, Fe, Al, Zn, Mn, and Cu in peach tree short life (PTSL) trees were compared to concentrations in apparently healthy trees in the same orchard. Leaf and stem concentration of K were significantly less and concentrations of Fe and Al were significantly greater in PTSL trees than healthy trees. Leaf concentrations of Ca and Mg and stem concentrations of N, P, and Cu were also significantly less in PTSL trees than healthy trees. Increased levels of Fe and Al and a K:Fe ratio of less than 150:1 in the leaves and stems was associated with PTSL.

There were no detected differences in prunasin, amino acid, or sugar content of PTSL and healthy trees in leaf and stem samples, but significant differences in elemental content suggest some type of stress on the root system of PTSL trees.  相似文献   

16.
One and 3 yr old needles of (Picoa abies [L.] Karst) were analyzed for mineral content and to determine the main nutrients and pollutants. In the Bavarian Alps 70 adult spruce trees were selected along an altitudinal gradient on seven stands from 800 to 1720 m above sea level. The samples, collected at different times of the year, came from the tops of the crowns. The needle analysis showed a severe P and a mild N deficiency. Samples which were washed with chloroform have significantly lower Fe and Ph contents. The low S concentrations of the needles exclude a burden by air pollution caused by SO2.  相似文献   

17.
Element composition of leaves and wood from healthy and declining beech (Fagus sylvatica L.) growing on SO2-polluted sites in the NE-Bavarian Mountains was studied. The wood and foliar Mg contents was significantly lower for declining than for healthy beech. Within the period between 1956 and 1985 the Mg concentrations in year rings of moderately damaged (declining site) and healthy beech declined significantly. No such change was observed for severely damaged beech (declining site), indicating that the Mg supply of those trees had reached a minimum already before 1956. Symptoms of forest decline, however, appeared first in the late seventies and early eighties. It is assumed that the decrease of the Mg concentration in year rings of healthy and moderately declining trees during the past three decades was caused by increasing acid emissions. The significant increase of the wood S contents especially at the declining high elevation site confirms this assumption.The decrease of the wood Mg contents was paralleled by a decrease of the annual increments in diameter for healthy and declining beech, which started in 1972 and became accelerated in 1976. The reduction of growth in the early seventies at the high elevation site coincided with an elongation of chimneys at power stations and steel works and higher filtering of basic dust relative to acid emissions. In the extremely hot and dry summer 1976 drought and a drastical drop of soil pH due to an excess nitrification are supposed to have accelerated the declining of growth and Mg availability. We, therefore, believe that the long-term acid input and the accelerated soil internal H+ production due to an excess nitrification are mainly responsible for the sustained symptoms of forest decline in the NE-Bavarian Mountains during the late seventies and early eighties.  相似文献   

18.
《Journal of plant nutrition》2013,36(10):2315-2331
ABSTRACT

Split root solution culture experiments were conducted to study the effects of the rare earth element lanthanum (La) on rice (Oryza sativa) growth, nutrient uptake and distribution. Results showed that low concentrations of La could promote rice growth including yield (0.05 mg L?1 to 1.5 mg L?1), dry root weight (0.05 mg L?1 to 0.75 mg L?1) and grain numbers (0.05 mg L?1 to 6 mg L?1). High concentrations depressed grain formation (9 mg L?1 to 30 mg L?1) and root elongation (1.5 mg L?1 to 30 mg L?1). No significant influence on straw dry weight was found over the whole concentration range except for the 0.05 mg L?1 treatment. In the pot and field experiments, the addition of La had no significant influence on rice growth.Lanthanum had variable influence on nutrient uptake in different parts of rice. Low concentrations (0.05 mg L?1 to 0.75 mg L?1) increased the root copper (Cu), iron (Fe), and magnesium (Mg), and grain Cu, calcium (Ca), phosphorus (P), manganese (Mn), and Mg uptake. High concentrations (9 to 30 mg L?1) decreased the grain Ca, zinc (Zn), P, Mn, Fe and Mg, and straw Ca, Mn, and Mg uptake. With increasing La concentration, root Zn, P, Mn, Cu, and Ca concentrations increased, and grain Ca and Fe, and straw Mn, Mg, and Ca concentrations decreased. Possible reasons are discussed for the differences between the effects of La in nutrient solutions and in pot and field experiments.  相似文献   

19.
The effect of increasing manganese (Mn) concentrations on calcium (Ca), potassium (K), magnesium (Mg), sodium (Na), and phosphorus (P) absorption and translocation was studied in rice (Oryza sativa L. cv. Safari), before and after the end of mobilization of seed reserves. Rice plants were grown over a 15-, 21-, and 28-day period in nutrient solutions containing Mn concentrations varying between 0.125 and 32 mg L?1. It was found that increasing Mn concentrations in the nutrient solution was coupled to an increasing net uptake, total shoot accumulation, and root and shoot contents of this metal during all the experimental periods. Concerning the translocation rates, in 15-day-old plants a decrease was found after the 2 mg L?1 Mn treatment, but from the 21st day onward an increase was found until the highest treatment. The modulating action of Mn in macronutrient accumulation displayed different patterns among the experimental periods. In the root tissues of 15-day-old plants, Ca decreased significantly until the 2 mg L?1 treatment and Na increased. In the shoots, the contents of P and Na decreased, but K and Mg showed significant increases. Until the 32 mg L?1 Mn treatment, the ratio between root and shoot concentrations of K and Mg decreased in these plants. A similar pattern was also found for Ca until the 2 mg L?1 Mn treatment. That ratio increased for Na. Plant total amount of Ca sharply decreased. Shoot total amount of Na and P also decreased, but the pattern of Ca increased until the 2 mg L?1 Mn treatment. The concentrations of K increased in the root tissues 21 days after germination, but the levels of Ca, Mg, Na, and P decreased. In the shoots, the concentrations of Ca and Mg decreased significantly. Until the 32 mg L?1 Mn treatment, the ratio between root and shoot concentration of Na and P increased, whereas those of Ca and Mg decreased. An increase was found for the plant and shoot total amount of Ca, K, and Mg until the last Mn treatment, but an opposite trend was found for Na and P. Additionally, until the 32 mg L?1 Mn treatment, an increase was found for the proportions of Ca and Mg translocated to the shoot, but an opposite trend was detected for P. It was concluded that before and after the end of the mobilization of seed reserves, the net uptake rate of Ca is reversed, and, moreover, a similar trend is shown for the net translocation of Mg. A major implication of this process is the alteration of the related pattern for shoot accumulation. Eventually a different selectivity of the K+:Na+ ratio is also developed in the roots.  相似文献   

20.
The effects of different levels of arsenic (As) and salinity on bean plant (Phaseolus vulgaris L., cv. Buenos Aires) nutrition were investigated. We studied the processes of absorption and accumulation of macronutrient elements: nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg). The experiment was performed in soilless culture at two levels of As: 2 and 5 mg AsL‐1 (added as sodium arsenite, NaAsO2), and three saline levels [only sodium chloride (NaCl) was added]: 1, 2, and 4 dS‐m‐1. Sodium arsenite and NaCl significantly affected macronutrients allocation within bean plant at concentration levels used in this study. Arsenite depressed K, Na, and Mg concentrations in root, whereas root N, and Ca levels were increased. Nitrogen, P, K, and Na concentrations were significantly higher in As‐stressed plants compared with controls. The addition of NaCl increased Ca concentration in roots and decreased that of K. Salinity tended to increase leaf concentrations of K, Na, Ca, and Mg; whereas leaf N and P levels decreased with increasing salinity.  相似文献   

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